Chris Mosby at myITforum.com

Last week, I received a tremendous reader response to a post I wrote about a security update from Microsoft that silently installed a "Microsoft .NET Framework Assistant" add-on for Firefox that was difficult and risky for users to uninstall. Given the emotional buttons this subject pushed among a large number of readers, I've put together a brief update along with some information provided in the comments to the previous post.

Since that posting, someone pointed out that Microsoft has issued a patch in an apparent bid to appease those who have cried foul about this silently installed add-on. The patch is available and detailed at this link here. The update patches Windows systems so that the add-on installed by Microsoft can be successfully uninstalled without the user having to manually edit the Windows registry. (While editing the registry isn't all that difficult, a misstep can cause serious problems and it is a task Microsoft does not recommend lightly for the Average Joe PC user).

From the Microsoft advisory:

To properly update the .NET Framework Assistant, this update must be applied while the extension is enabled in Firefox. To remedy the result of installing this update while the extension was disabled, uninstall the update, re-enable the extension, and reinstall the update. Updates to the .NET Framework Assistant may include updates to the Windows Presentation Foundation Plug-in for Firefox causing it to be enabled upon its initial update.

So, in short, if you've chosen to merely click the "disable" button on this add-on instead of manually removing it by editing the Windows registry, you will need to re-enable the add-on before applying this fix.

After you've downloaded and installed the update, if you check Add-ons from the Firefox menu you'll notice that the .NET Framework Assistant add-on is now at version 0.0.0 (from 1.0), and that you are prompted to restart the browser (see below).

Upon restart, check your Add-ons again and you'll see that the add-on has been reinstalled so that the uninstall tab is no longer grayed out. You still have to click the uninstall tab and "yes" to the "are you sure" prompt, and then restart Firefox again to fully banish the thing.

The Service Pack 1 patch for .NET that originally installed this add-on also installs a Firefox plug-in called the "Windows Presentation Foundation plug-in for Mozilla browsers." If you had disabled that plug-in after installing the .NET Service Pack 1, note that installing this patch re-enables that plug-in.

Interestingly, one reader forwarded me this link at Bugzilla -- Mozilla's bug tracking database. It's an inside look at debate among Firefox developers over whether the ability of third party applications to install their own add-ons and block users from easily uninstalling them should be considered a bug.

One final note, as Microsoft and a number of readers have noted, the uninstall button for the original .NET add-on that started all this is not grayed out for Windows 7 users, so those users can remove this add-on without going through all this.

By Brian Krebs  |  June 3, 2009; 9:30 AM ET
Categories:  From the Bunker , New Patches  | Tags: microsoft patch firefox add-on Share This:  E-Mail | Technorati | Del.icio.us | Digg | Stumble Previous: Security Updates for iTunes, QuickTime